--- old/src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.hpp	2014-12-10 15:32:32.212077870 +0100
+++ new/src/share/vm/gc_implementation/parallelScavenge/parallelScavengeHeap.hpp	2014-12-10 15:32:32.112081234 +0100
@@ -64,7 +64,7 @@
   // The task manager
   static GCTaskManager* _gc_task_manager;
 
-  void trace_heap(GCWhen::Type when, GCTracer* tracer);
+  void trace_heap(GCWhen::Type when, const GCTracer* tracer);
 
  protected:
   static inline size_t total_invocations();